We propose to create a Collaboratory Coordinating Center (Collaboratory CC) to work with the NIH to produce, document, and disseminate standards, and to create durable infrastructure that facilitates multicenter studies and reuse of data. The Collaboratory CC will be based at Duke University, with participation by the Harvard Pilgrim Health Care Institute at Harvard Medical School, the Group Health Research Institute, Johns Hopkins University and the Center for Medical Technology Policy. Our investigators have established multi-center research collaborations using electronic health records (EHRs), convened stakeholders to transform clinical trials, developed new regulatory approaches, and pioneered the use of patient-reported outcomes (PROs) in clinical research. This team has extensive experience in conducting both conventional and cluster randomized clinical trials, quasi-experimental studies, and observational studies across the spectrum of health systems, including integrated delivery systems and health plans, academic health and science systems, and private practices. The critical importance of this effort is reinforced by recent literature demonstrating that the vast majority of medical decisions are not supported by high quality evidence and that the clinical trials system is focused on small trials without sufficient power to fully inform practice or policy. In the face of this evidence gap the Institute of Medicine has called for a transformation of clinical trials rather than incremental improvements. This transformation should deal with the current fundamental separation of the conduct of clinical trials from the delivery of clinical care by involving practitioners and their health systems in th design and interpretation of trials, providing the broad education needed to enhance the value of practitioner participation and using the data collected as part of healthcare delivery as the core data source for the full spectrum of clinical research, from registries to observational studies an randomized trials. We believe that we are at a tipping point, that if propelled by a powerful Collaboratory effort, will enjoin multiple public and private entities towards the common goal of a Learning Health System. At the end of the five-year funding period, new policies, procedures, governance capabilities, and a substantial infrastructure will enable larger, simpler, less expensive and more relevant clinical trials that will be an integral component of the healthcare system.